Type II diabetes usually develops in people over 40, and it often runs in families. For instance, Pattie LaBelle was diagnosed with Type II diabetes at age 50, and her mother died of the disease.

Type II diabetes is often linked to obesity and inactivity and can often be controlled with diet and exercise alone. Type II diabetics sometimes use insulin, but usually oral medications are prescribed if diet and exercise alone do not control the disease.

Malfunction in Glucose Metabolism

In a normal body, carbohydrates (sugars and starches) are broken down in the intestines to simple sugars (mostly glucose), which then circulate in the blood, entering cells, where they are used to produce energy. Diabetics respond inappropriately to carbohydrate metabolism, and glucose can't enter the cells normally.

Insulin -- a hormone that is made in the pancreas and released into the bloodstream and carried throughout the body -- enables the organs to take sugar from the blood and use it for energy. If body cells become resistant to insulin's effect or if there isn't enough insulin, sugar stays in the blood and accumulates, causing high blood sugar. At the same time, cells starve because there's no insulin to help move sugar into the cells.

Diabetes is diagnosed by measuring blood sugar levels. This can begin with a urine test sampled for glucose because excess sugar in the blood spills over into the urine. Further testing involves taking blood samples after an overnight fast. Normal fasting blood glucose levels are between 70 mg/dl and 105 mg/dl; a fasting blood glucose measurement greater than 140 mg/dl on two separate occasions indicates diabetes.

Diabetes can result in many complications, including nerve damage, foot and leg ulcers, and eye problems that can lead to blindness. Diabetics also are at greater risk for heart disease, stroke, narrowing of the arteries, and kidney failure. But evidence shows that the better the patient controls his or her blood sugar levels, the greater the chances that the disease's serious complications can be reduced.